isaac_ros_h264_decoder

Set Up Development Environment

1. Set up your development environment by following the instructions in getting started.

2. Clone isaac_ros_common under ${ISAAC_ROS_WS}/src.

   cd ${ISAAC_ROS_WS}/src && \
      git clone https://github.com/NVIDIA-ISAAC-ROS/isaac_ros_common.git
   

3. (Optional) Install dependencies for any sensors you want to use by following the sensor-specific guides.

   Warning

   We strongly recommend installing all sensor dependencies before starting any quickstarts. Some sensor dependencies require restarting the Isaac ROS Dev container during installation, which will interrupt the quickstart process.

Download Quickstart Assets

1. Download quickstart data from NGC:

   Make sure required libraries are installed.

   sudo apt-get install -y curl tar
   

   Then, run these commands to download the asset from NGC.

   NGC_ORG="nvidia"
   NGC_TEAM="isaac"
   NGC_RESOURCE="isaac_ros_assets"
   NGC_VERSION="isaac_ros_h264_decoder"
   NGC_FILENAME="quickstart.tar.gz"
   
   REQ_URL="https://api.ngc.nvidia.com/v2/resources/$NGC_ORG/$NGC_TEAM/$NGC_RESOURCE/versions/$NGC_VERSION/files/$NGC_FILENAME"
   
   mkdir -p ${ISAAC_ROS_WS}/isaac_ros_assets/${NGC_VERSION} && \
       curl -LO --request GET "${REQ_URL}" && \
       tar -xf ${NGC_FILENAME} -C ${ISAAC_ROS_WS}/isaac_ros_assets/${NGC_VERSION} && \
       rm ${NGC_FILENAME}
   

Build isaac_ros_h264_decoder

Run Launch File

Visualize Results

1. Open a new terminal inside the Docker container:

   cd ${ISAAC_ROS_WS}/src/isaac_ros_common && \
      ./scripts/run_dev.sh
   

2. Visualize and validate the output of the package:

   ros2 run image_view image_view --ros-args -r image:=/left/image_uncompressed
   

   ros2 run image_view image_view --ros-args -r image:=/right/image_uncompressed
   

Symptom

Launching the decoder node using ros2 launch isaac_ros_h264_decoder isaac_ros_h264_decoder_rosbag.launch.py, produces the below error message:

x86_64 Platform:

[component_container_mt-2] 2023-04-04 22:19:02.609 WARN  /workspaces/isaac_ros-dev/ros_ws/src/isaac_ros_compression/isaac_ros_h264_decoder/gxf/codec/components/decoder.cpp@310: Decoder output is empty, current frame will be dropped

Jetson Platform:

[component_container_mt-2] 2023-04-04 06:39:57.766 WARN  gxf/std/greedy_scheduler.cpp@235: Error while executing entity 20 named 'KIWPUYFVJT_decoder_response': GXF_FAILURE
[component_container_mt-2] [ERROR] (/usr/src/jetson_multimedia_api/samples/common/classes/NvV4l2ElementPlane.cpp:178) <dec0> Capture Plane:Error while DQing buffer: Invalid argument
[component_container_mt-2] 2023-04-04 06:39:57.766 ERROR /workspaces/isaac_ros-dev/ros_ws/src/isaac_ros_compression/isaac_ros_h264_decoder/gxf/codec/components/decoder_request.cpp@530: Failed to dequeue buffer from capture plane
[component_container_mt-2] 2023-04-04 06:39:57.766 ERROR gxf/std/entity_executor.cpp@509: Failed to tick codelet  in entity: KIWPUYFVJT_decoder_response code: GXF_FAILURE
[component_container_mt-2] 2023-04-04 06:39:57.766 ERROR gxf/std/entity_executor.cpp@203: Entity with eid 35 not found!

Solution

You may see these errors when decoder receives P-frames first. Decoder can not decode P-frames until it has received the first I-frame. You can start the decoder before playing the rosbag to avoid these errors.

Usage

ros2 launch isaac_ros_h264_decoder isaac_ros_h264_decoder.launch.py

ROS Parameters

ROS Topics Subscribed

ROS Topics Published

Output Interpretations

1. The isaas_ros_h264_decoder package outputs a uncompressed image with the same resolution as the original image. The output image will be in RGB8 format.